The Federal Aviation Administration (FAA) continues to require airborne Automatic Dependent Surveillance-Broadcast (ADS-B) applications to provide improved benefits to operators. One of the benefits of ADS-B is the In-Trail Procedures (ITP). In addition to increasing flight crew awareness of the traffic around them, ITP displays offer information for safely climbing or descending through altitudes.
Currently, datalinking allows digital text messaging between controllers and pilots. ITP using Controller-Pilot Datalink Communication (CPDLC) for datalinking requires the use of structured and defined message sets consisting of uplink and downlink messages. A major concern with using CPDLC in general is the amount of heads-down time in the cockpit. It is critical that heads-down time be mitigated. Part of this mitigation is a requirement that pilots be able to quickly find, compose, and send ITP requests to Air Traffic Control (ATC). Also, wrongly formulating the ITP datalink messages by, for example, not adhering to the standard message formats, not providing all required ITP information, or entering the wrong variables will result in communication errors and delays. Evidence of this problem is mentioned in a NASA study titled “Enhanced Oceanic Operations Human-In-The-Loop In-Trail Procedure Validation Simulation Study” (NASA/TP-2008-215313).
Currently a touch panel display on an Electronic Flight Bag (EFB) display device is used for composing and sending ITP altitude change requests to ATC. The setting up and sending of an ITP clearance via an Electronic Flight Bag (EFB) device is cumbersome and because free text is used, it can be prone to error.